How do I measure my dog for a collar and harness?
When measuring your dog for a collar, measure the circumference of the dog’s neck and be sure to place two fingers between the dog and the measuring tape you use.

When measuring your dog for a harness, measure the girth around the dog’s
body behind the two front legs. Add two inches or five centimetres to the
measurement. Both the collar and harness should fit snugly but not too tightly.

How do I put the Step-in Harness on my dog?
Have your dog step into the harness and then bring the harness over the shoulders so that the buckle clips on the shoulders on the dog’s back. You should have the two back pieces coming up from under the dog and directly behind the dog’s two front legs. The two front pieces should come from the dog’s chest over his shoulder blades to his back where the buckle is clipped. The center piece should run from behind the legs up the front of the chest.